Her marriage to Fumihito in 1990 furthered the trend of Japanese imperial males marrying middle class commoners of academic prominence in earlier and current generations.

Preceding Fumihito and Kiko's investiture as Crown Prince and Princess, the ongoing Japanese imperial succession debate had resulted in some politicians holding a favorable view on rescinding agnatic primogeniture imposed by World War II allies on the constitution of Japan.

Hisahito's cousin and Emperor Naruhito's only child, Princess Aiko, remains at present legally ineligible to inherit the throne, while debate about the possibility of having future empresses regnant continues.

[2] As active working members of the imperial family, Kiko and Fumihito's schedule includes attending summits, and organizational and global event meetings.

No marriage date would be set until the official one-year mourning period ended for Fumihito's grandfather, Emperor Hirohito, who had died in January 1989.

[5] As the second woman from a middle-class and academician background to marry into the imperial family after her mother-in-law Empress Michiko, she was given the nickname "the apartment princess" by the media.

[9] She attends the "Sign Language Speech Contest for High School Students" held every August, and "Praising Mothers Raising Children with Hearing Impairments" every December.

[11] In March 2013, Kiko was granted a PhD degree in Psychology at the Graduate School of Humanities and Sciences, Ochanomizu University, for her dissertation entitled "Knowledge, perceptions, beliefs and behaviors related to tuberculosis: A study based on questionnaire surveys with seminar participants of the National Federation of Community Women's Organizations for TB Control and female college students.

"[10] Since 1997, Prince Fumihito and Princess Kiko and their children have maintained a principal residence on the grounds of the Akasaka Estate in Motoakasaka, Minato, Tokyo.

The couple have three children (two daughters and one son): The Prince and Princess are called upon to meet with important overseas visitors to improve diplomatic relations.

[36] The princess also had carpal tunnel syndrome osteoporosis aggravated by child-nursing, a symptom common among middle-aged women, her doctor revealed on 14 December 2007.

[37] In late 2023 it was reported that Kiko was suffering from a gastrointestinal illness which prevented her from eating "normal meals" though an endoscopy performed on her in January 2024 found no abnormalities.